Patent document EP 2 447 728 A1 discusses a measuring system for a battery cell. The battery cell may be loaded with an impedance, it being possible to switch the load on or off via a switch that is operated in a clocked manner. A voltage drop across the impedance is low-pass filtered and subsequently evaluated.
Electrical energy stores such as lithium-ion batteries, for example, are used in numerous areas. They are used, for example, as traction batteries in electric vehicles. The storage capacity of the individual cells in such energy stores may vary over their service life. Checking the storage capacity is of great interest for evaluating the cells in such an energy store.
Currently, the cells of an energy store, such as lithium-ion battery cells for example, must be completely charged and discharged in order to obtain precise and reliable information about their storage capacity. Alternatively, it is also possible for data of an existing battery management system to provide information about the state and the storage capacity of the individual battery cells. For this purpose, however, the battery management system must be adjusted precisely to the individual cells of such an energy store.